Layer 2 Routing Instance Types
Although routing instances are primarily intended to maintain separation of tables and protocols at Layer 3 (mirroring the traditional IP network separation at Layer 3), many aspects of routing instances make them convenient to use for Layer 2 applications and architectures as well. In Layer 2 applications, routing instances still help to maintain table, interface, and customer insulation, but with regard to media access control (MAC) addresses and VLAN tags as much as IP addresses.
You can configure three types of routing instances (instance-types) in Layer 2 networks on MX Series routers, as described in the indicated sections:
- layer2-control (MX Series routers only)—Layer 2 control protocol routing instance. For configuration information, see Configuring Layer 2 Protocol Tunneling, Configuring BPDU Protection on Individual Interfaces, and Configuring BPDU Protection on All Edge Ports.
- virtual-switch (MX Series routers only)—Virtual switch routing instance. For configuration information, see Configuring a Layer 2 Virtual Switch.
- vpls—Virtual private LAN service (VPLS) routing instance. For configuration information, see Configuring a Bridge Domain.
The other five types of routing instances are configured only for Layer 3 networks, and are described in the indicated Junos configuration guide:
- forwarding—Forwarding instance. For more information, see the Junos OS Routing Protocols Library for Routing Devices.
- l2vpn—Layer 2 VPN routing instance. For more information, see the Junos OS VPNs Library for Routing Devices.
- no-forwarding—Nonforwarding routing instance. For more information, see the Junos OS Routing Protocols Library for Routing Devices.
- virtual-router—Virtual routing instance. For more information, see the Junos OS Routing Protocols Library for Routing Devices.
- vrf—VPN routing and forwarding (VRF) instance. For more information, see the Junos OS Routing Protocols Library for Routing Devices.
